Cigarette packets, whether the type called soft or American or else the hinged lid type, have the inner wrapper, that is the wrapper in direct contact with the cigarettes, made of foil or more precisely a material made up of a paper backing covered on one side with a film of foil.
It is usual for the rectangular lengths of foil that go to make up these inner wrappers to be taken off a continuous roll by means of a cutting device made basically from a couple of blades counter rotating at the same peripheral speed and in reciprocal periodic contact along the roll feed plane.
It is also known that the use of ordinary cutting devices in very high speed cigarette packers, machines of the type described for example in applicant's U.S. Pat. Nos. 3,628,309 and 3,968,115, application 611,885, leads to or even heightens various drawbacks.
At high running speeds particularly serious consequences stem from adhesive forces between the metal foil film and the cutting edge of the blade which is going to sever the roll on the metal coated side.
This drawback which can lead to deviation of the lengths from feed line to packaging mechanisms has been solved as may be seen from applicant's U.S. patent application No. 721,528 by giving the blade a peripheral speed at least twice that with respect to the second blade which is going to cut the roll on the side of the paper backing material.
Indeed the adhesive phenomenon also occurs between the blade cutting the metal film and metal particles or fragments shed from the roll in the course of this operation.
As these fragments accumulate, the cutting capacities of the device gradually lower until along the lines of separation between length and length there soon appear creases or tears.
To resume proper running conditions at this point means performing with the packer in stay position a close and time-consuming cleaning operation on the cutting device.